镍基双合金扩散偶的拉伸性能研究

THE TENSILE PROPERTIES OF DIFFUSION COUPLE OF NICKLE-BASE DUAL-SUPERALLOY

采用热等静压(HIP)扩散连接工艺,获得了镍基单晶高温合金与粉末高温合金的扩散偶。研究了热等静压和热处理工艺对扩散偶的组织和拉伸性能的影响。结果表明,不同温度热等静压的扩散偶均实现了冶金结合,瞬时拉伸断口位置处于DD402侧,断裂面为{111}滑移面。随着HIP温度升高,DD402母材的γ′相粒子粗化,FGH95粉末合金母材的再结晶晶粒长大;1 166℃HIP扩散偶热处理后,FGH95粉末合金的γ′相由晶界大尺寸γ′相、晶粒内中等尺寸的和细小的γ′相组成。扩散偶试样的650℃抗拉强度受HIP温度影响小,而屈服强度随着HIP温度升高而降低。

The diffusion couple of single crystal DD402 and FGH95 were obtained by hot isostatic pressing （HIP） diffusion bonding. The influence of HIP and HT on the tensile properties and microstructure of diffusion couples were investigated. The results indicated that all diffusion couples are bonded metallurgically for different HIP processing, and the location of tensile fracture along the slide plane of {111}is in the side of single crystal DD402; the γ′ phase of DD402 and recrystallized grain of FGH95 are grown up with raise of HIP temperature. For diffusion couple bonded at 1 166℃ HIP, the γ′ phase of FGH95 was consist of big γ′ in boundary.middle γ′ and fine γ′ in grain after HT; for diffusion couples, the HIP temperature do not affect obviously the tensile strength at 650℃ , but the yield strength decrease with increasing HIP temperature.